Portable battery charger



FIG. 1 is a front perspective view of a portable battery charger showing our new design;

FIG. 2 is a top elevation view thereof;

FIG. 3 is a bottom elevation view thereof.

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a front elevation view thereof; and,

FIG. 7 is a rear elevation view thereof.

The broken line representations of portions of the portable battery charger in FIGS. 1 to 7 are shown for illustrative purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a portable battery charger, as shown and described. 